1. Field of the Invention
The present invention relates generally to molded countertops for use particularly in kitchens and bathrooms and, more particularly, to a novel molding process for producing a finished solid surface countertop.
2. Description of the Prior Art
Countertops, table tops and the like have long been made from materials such as wood, metal and stone. Wood is the easiest material to fabricate; but, it is easily cut or chipped, not sanitary, and does not resist high temperatures. Metal and stone are very durable, and resistant to temperature extremes; but they are difficult to fabricate. In addition, all such materials are relatively expensive. As a consequence, the industry has turned to the use of synthetic materials for the fabrication of countertops. Such materials are generally based upon organic polymers.
Various processes and procedures are known in the art for producing solid surface, fiber reinforced polymer, and cultured marble countertops. The term solid surface pertains to a material where there is no painted or laminated skin or outer surface, and in such materials, small scratches and burns, etc. can be sanded or buffed out.
The industry for solid surfacing began approximately twenty-five years ago when Dupont Inc. developed a high quality surfacing material known commercially as Corian.RTM.. Since the early 1980's, several major manufacturers have developed their own brand of solid surface products. For the most part, these products are expensive to produce and are distributed in nominal sized sheets that are fabricated by the lengthy process of cutting the sheet into the desired countertop shape and re-bonding by adhesive or the like to a substrate surface.
More recently, spray-on solid surface materials, such as those commercially known as Safas.RTM. and Omniplex.RTM., have come into use. In one known application, these spray-on materials are coated over an inexpensive substrate, such as a particle board or other material which is already shaped in the desired fashion. Once the spray-on material has dried, a lengthy sanding and finishing process is required to bring the finish up to the desired quality, and there still is a need to remove pinholes exposed during this process, which are a by-product of the fabrication process of coatings of this type. Such sanding and finishing processes are necessary for providing an acceptable finish and have thus far proven too labor intensive to be workable in today's production countertop industry.
Direct molding processes are very attractive for the fabrication of countertops, sinks, basins and such units, since techniques of this type permit fabrication of a finished shape having good surface quality. One molding process involves the so-called cultured marble materials. These include an outer gel coat polymer layer, comprised of a relatively soft, unfilled resin, disposed over a faux-veined, mineral-filled resin base which attempts to provide the appearance of stone. This second layer may be backed with an additional layer of low cost material. Cultured marble articles are not very durable, since the gel coat is readily scratched, chipped or delaminated. Also, scratches or chips cannot be readily sanded out of the gel coat because it is soft and fairly thin. Additionally, moisture or thermal shock can cause cultured marble articles to delaminate, crack or wrinkle, particularly if there are any breaks in the gel coat. As will be detailed hereinbelow, the present invention provides a method whereby a composite countertop or the like may be fabricated by a molding process so as to have a surface comprised of a relatively thick body of organic resin based, high quality, solid surface material, which provides durability and aesthetics, and which is supported upon a durable, relatively low cost body of substrate material. Furthermore, the present invention eliminates the need to grind down or otherwise undertake extensive finishing steps to produce a high quality surface. These and other advantages of the present invention will be apparent from the drawings, discussion and description which follow.